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Updated: Jun 11, 2025

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Scanning-probe Single-electron Capacitance Spectroscopy
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表面电荷测量的相位依赖性 在交流电压下在C4F7N/CO2的环氧绝缘体上
Shuangying Li1, Yu Gao1, Di Lu1
1School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China.
Polymers
|September 28, 2024
概括
在AC GIS中,甲 (C4F7N) 和二氧化碳气体混合物需要了解环氧树脂电荷分布. 这项研究揭示了绝缘体上的负电荷积累,受交流电压持续时间的影响,但不是切断时的相角.
科学领域:
- 电气工程 电气工程
- 材料科学 材料科学 材料科学
- 等离子体物理学的物理学
背景情况:
- 七甲 (C4F7N) 和二氧化碳的二进制气体混合物正在为交流气体绝缘开关设备 (GIS) 获得关注.
- 了解环氧树脂上的气体固体界面电荷分布对于GIS应用至关重要.
- 这些系统中充电行为的相位依赖性尚未完全理解.
研究的目的:
- 为了研究在交流电压下的环氧树脂绝缘体上的表面电荷分布特征.
- 分析交流电压参数 (相角,持续时间) 对电荷积累的影响.
- 在GIS环境中理论分析C4F7N/CO2混合物的电荷传输机制.
主要方法:
- 模拟了一个同轴电极结构,代表了GIS.
- 在一个缩小尺寸的环氧绝缘体上研究了表面电荷分布.
- 分析了切断相角和交流电压持续时间对电荷行为的影响.
- 在AC条件下理论分析了电荷传输机制.
主要成果:
- 观察到明显的负电荷斑点,特别是金属颗粒的存在.
- 在绝缘体表面积累的负电荷明显超过了正电荷.
- 最大表面电荷密度和累积电荷最初增加,然后随着时间的推移而减少.
- 阶段角显示在电压切断时刻对表面电荷分布的影响微不足道.
结论:
- 这项研究为AC GIS的C4F7N/CO2混合物中的气体固体接口电荷行为提供了关键的见解.
- 负电荷积累是一个主要的现象,受电压持续时间的影响.
- 这些发现对于设计使用这些先进气体混合物的可靠和安全的GIS设备至关重要.
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